If you can get a 100 percent refund, it wouldn't be a bad option. The last two Macworlds have had an Apple TV release, so it wouldn't shock me for another one. The fact that it goes a year without any hardware updates or price reductions is kind of annoying since we all know how hard drive prices can drop.
If I had the ear of Steve Jobs, I'd tell him to put a DVD drive in it, allow for 3.5" hard drives, allow external USB drives, and put a decent GD remote with it. Whenever they get on the Blu-ray bandwagon, have a Blu-ray option. Allow Netflix streaming.
Unfortunately, here's what I see happening: Same design, maybe a 60GB hard drive, HD movies for purchase (at $25 each). After spending a year figuring out that people aren't going to pay that much for HD downloads that are inferior to Blu-ray, they'll start putting BD drives on computers about 2 years later than everybody else.
Either that or Jobs will go completely bananas and do away with optical drives on EVERY computer and make you download EVERYTHING from iTunes or Apple.com. If you think that's farfetched, gaze at the MacBook Air.